Stop motion device with selective indicator

ABSTRACT

A stop motion system for multi-thread textile machines includes a number of thread slack-detection switches disposed in parallel and each having an indicator lamp and a diode in series with the switch. A voltage source and a stop motion relay are in series with the switches and the voltage source produces a potential through any closed switch and its associated lamp and diode greater than the breakover voltage for the diode. Each diode, however, is a four layer diode so that its sustaining voltage is very much less than its breakover voltage. In this way, the first diode to conduct reduces the potential available across any of the other diodes to the sustaining voltage so that only the first detector circuit activated will be effective to provide an indication of malfunction.

United States Patent Cook et al. 1 Apr. 3, 1973 54 STOP MOTION DEVICEWITH 3,324,899 6/1967 Stagg .439/553 SELECTIVE INDICATOR 3,382,3715/1968 Feldman ....307/ 25s x 3,576,560 4/1971 Vermeulen ..340/259 [75]Inventors: Harold E. Cook, Lanett; Harold H.

Lani, Fairfax both of Primary ExaminerDavid L. Trafton' [73] Assignee:Batson-Cook Company, West Point, Attorney-Edward Tayk Newton et a 57ABSTRACT 22 F'l d: D 15 1971 1 1 6 cc A stop motion system formulti-thread textile [21] Appl- No.1 208,096 machines includes a numberof thread slack-detection switches disposed in parallel and each havingan in- {521 U S Cl 340/415 139/353 307/258 dicator lamp and a diode inseries with the switch. A 307/324: 340/259 340/419 voltage source and astop motion relay are in series Int Cl G68) 21/00 with the switches andthe voltage source produces a potential through any closed switch andits associated [58] held of Search igg gj ygggifigg lamp and diodegreater than the breakover voltage for the diode. Each diode, however,is a four layer diode so that its sustaining voltage is very much lessthan its [56] References cued breakover voltage. In this way, the firstdiode to con- UNTED STATES PATENTS duct reduces the potentialavailableacross any of the other diodes to the sustaining voltage so that onlythe 3,081,449 3/1963 Wernlund ..340/415 first detector circuit activatedwill be effective to pro- 3,147,464 Spielman vide an indication ofma1functi0n 3,309,583 3/1967 Ziller et al. ..307/324 X 3,321,755 5/1967Cooke ..340/419 5 Claims, 2 Drawing Figures I L 2* I 50 4 (PATENTEUAPM1975 FIG. I

IN VENTORS BY M f ATTORNEY BACKGROUND OF THE INVENTION A great manyarrangements for effecting stop motion of multi-thread textile machineshave been proposed each of which is effective to stop the machine when athread becomes slack. If no means is provided in the detector circuitryas to which of the threads has become slack, the operator must hunt tofind which, if any, of the threads has caused the stop motion mechanismto become effective. In some instances, a malfunction arises at anotherportion of the machine and a thread is not at fault at all and for thisreason it has become conventional to provide indicating lamps toindicate which, if any, of the threads have in fact become slack so asto cause stopping of the machine. However, in such systems, it oftenhappens that more than one thread will become slack and it would be ofinterest for the purpose of taking the proper corrective action, to knowwhich of the threads first became slack and thus activated the stopmotion device. Prior devices make no such provision.

BRIEF SUMMARY OF THE INVENTION Accordingly, it is of principal concernin connection with the present invention to provide an improved stopmotion device for multi-thread textile machines wherein selectiveindication of the first thread to have become slack is made. Morespecifically, this arrangement in connection with the present inventionis effected by disabling all other thread slack-detecting circuits onceany one of them has been activated to stop the motion of the machine.

Specifically, the selective indication according to the presentinvention is effected by utilizing four layer diodes in each of thedetector circuits, all. the detector circuits being disposedelectrically in parallel so that when any one of them is activated, theparticular diode in question will effectively prevent conduction of anyof the other diodes by reason of the fact that the sustaining voltagefor the conducting diode is very much less than the breakover voltagefor each of the diodes. An indicator lamp in each of the detectorcircuits thereby indicates which thread first became slack and themachine operator may immediately and more readily ascertain the natureand extent of the problem which caused stoppage of the machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing aconventional detector switch which may be utilized in connection withthe present invention; and

FIG. 2 is a circuit diagram illustrating the principles according to thepresent invention and utilizing the plurality of the switches shown inFIG. 1.

DETAILED DESCRIPTION OF THE INVENTION With reference more particularlyto FIG. I, one of the plurality of threads associated with a textilemachine is indicated by the reference character and a slack-detectingswitch therefor is indicated generally by the reference character 12.The detector switch comprises principally a drop wire indicatedgenerally by the reference character 14 and provided with an opening 16through which the thread 10 is passed. By means of the tension in thethread 10, the drop wire 14 is held in the inoperative, elevatedposition shown in FIG. I. The drop wire 14 includes a longitudinal slot18 through which a detector bar indicated generally by the referencecharacter 20 projects with the drop wire slot 18 normally centeredgenerally with respect thereto when in the elevated position as shown inFIG. 1. The upper end of the slot 18 is provided with a cam surface 22which is adapted to engage the upper contact member 24 of the detectorbar 20 in the event that the thread 10 becomes slack and the drop wire14 drops relative to the bar, the cam portion 22 assuring that the leg26 of the drop wire will positively be engaged against one side of thedetector bar 20. The purpose for this is to assure that the normallyopen contact which exists between the electrically conducting portion 24of the bar 20 and the electrically conducting portion 30 of 36 areelectrically connected respectively to the detector bar contact 22 andthe contact body 30 of the bar 20 so as to provide, for each threaddetector switch as sembly, suitable electrical connection forincorporation in the detector circuit hereinafter described.

It will be further understood that the detector switch assemblyillustrated in FIG. 1 is of entirely conventional nature and the detailsthereof form no part of the present invention. It will also beunderstood that other and different types of detector switches may beutilized in connection with the present invention, the embodiment ofFIG. 1 serving merely to illustrate a preferred and operative form ofdetector switch.

With reference to FIG. 2, the principles according to the presentinvention will be apparent therefrom and, in this Figure, a plurality ofdetector switches are diagrammatically illustrated and indicated by thereference characters 12 and will be seen to be connected electrically inparallel between the junctions 38 and 40 in FIG. 2. Thus, each detectorswitch 12 is pro,- vided in a separate detector circuit and each suchcircuit includes, in addition to the detector switch 12, a multi-layerdiode device 42 and an indicating lamp 44 all connected electrically inseries between the junctions 38 and 40 previously mentioned.

A suitable electrical energy source for the system is indicatedgenerally by the reference character 46 and is electrically connected inseries with a relay 48 from the junction 40 to the junction 48 therebyto be in electrical series with the parallel array of detector circuitspreviously described. The relay 48 includes a pair of normally closedswitch contacts 50 and a pair of normally open switch contacts 52 which,when the relay 48 is energized, are activated respectively to open andclosed conditions. The relay 48 actuates the stop motion effect on themachines, as by opening the contacts 50 and closing the contacts 52, thelatter contacts 52, when closed, preferably effecting the holding actionsuch that the machine does not automatically restart when the relay 48is subsequently deenergized, but requires, instead, deliberatemanipulation by the operator to disable the holding circuit so that themachine may be restarted. This, of course, is entirely conventionalarrangement and is provided for safety purposes.

The electrical energy source 46 which may be either a voltage or currentsource, normally impresses a voltage between the junctions 38 and 40which is sufficiently high to activate any one of the multi-layer diodes42 so that when any switch 12 is closed, its associated diode 42 willconduct thereby to complete the circuit through the relay coil and stopthe motion of the machine also to light the relevant indicator lamp 44.As stated, the diodes 42 are multi-layer devices and are preferably fourlayer diodes but which in any event exhibit a breakover voltage which issignificantly higher than their sustaining voltage so that once any oneof the diodes commences conduction, the voltage across the junctions 38and 40 is clamped to a voltage level very much less than the normalvoltage level at the junction 38 and which is less than that required topermit conduction of any of the other diodes 42 even if the associatedswitches 12 therefor happen to close. In this way, only the diode 42associated 'with the particular detector switch 12 at which a slackcondition of the thread first occurred will conduct and,correspondingly, only that associated indicator lamp 44 thereof will beenergized. Accordingly, the machine operator immediately is apprised ofjust exactly which thread effected the stoppage of the machine.

What is claimed is:

1. In a stop motion system for a multi-thread textile machine comprisingin combination:

a plurality of normally open detector switches connected in parallelbetween a pair of common junctions, any one of which switches may beclosed in response to slack in a thread associated therewith;

electrical energy source means for establishing a selected voltageacross said common junctions when all of said detector switches areopen;

a relay in series with said electrical energy source means and saidjunctions, said relay including switch means for stopping the machinewhen any of said detector switches is closed; an indicator device inseries with each of said detector switches; and diode means in serieswith each detector switch and associated indicator device for activatingthe associated indicator device and decreasing said selected voltageacross said junctions to a sustaining voltage value when any associatedone of said detector switches is closed, each diode means being amulti-layer device providing a break over voltage substantially greaterthan said sustaining voltage but less than said selected value so thatonly that indicator device associated with the firstclosed detectorswitch is activated. 2. In a stop motion system as defined in claim 1wherein each diode means is a four layer diode.

3. In a stop motion system as defined in claim 2 wherein each indicatordevice is a light source.

4. In a stop motion system as defined in claim 1 wherein said relayincludes first and second pairs of switch contacts, one for stoppingmotion of the associated machine and the other for holding the machineIn stopped condition, whereby removal of the fault associated with saidfirst-closed detector switch allows indication by another closeddetector switch without restarting the machine.

5. A slack thread detector and stop motion circuit for multi-threadtextile machines, comprising in combination:

a plurality of detector circuits connected in parallel;

and

a stop motion circuit connected in series with said detector circuits,the stop motion circuit including an electrical energy source impressinga selected voltage across said detector circuits;

each detector circuit including a normally open detector switch and amulti-layer diode in series therewith so that when any detector switchis closed, said selected voltage is clamped to a lesser valueineffective to allow conduction of any diode in the remaining detectorcircuits.

1. In a stop motion system for a multi-thread textile machine comprisingin combination: a plurality of normally open detector switches connectedin parallel between a pair of common junctions, any one of whichswitches may be closed in response to slack in a thread associatedtherewith; electrical energy source means for establishing a selectedvoltage across said common junctions when all of said detector switchesare open; a relay in series with said electrical energy source means andsaid junctions, said relay including switch means for stopping themachine when any of said detector switches is closed; an indicatordevice in series with each of said detector switches; and diode means inseries with each detector switch and associated indicator device foractivating the associated indicator device and decreasing said selectedvoltage across said junctions to a sustaining voltage value when anyassociated one of said detector switches is closed, each diode meansbeing a multilayer device providing a break over voltage substantiallygreater than said sustaining voltage but less than said selected valueso that only that indicator device associated with the first-closeddetector switch is activated.
 2. In a stop motion system as defined inclaim 1 wherein each diode means is a four layer diode.
 3. In a stopmotion system as defined in claim 2 wherein each indicator device is alight source.
 4. In a stop motion system as defined in claim 1 whereinsaid relay includes first and second pairs of switch contacts, one forstopping motion of the associated machine and the other for holding themachine in stopped condition, whereby removal of the fault associatedwith said first-closed detector switch allows indication by anotherclosed detector switch without restarting the machine.
 5. A slack threaddetector and stop motion circuit for multi-thread textile machines,comprising in combination: a plurality of detector circuits connected inparallel; and a stop motion circuit connected in series with saiddetector circuits, the stop motion circuit including an electricalenergy source impressing a selected voltage across said detectorcircuits; each detector circuit including a normally open detectorswitch and a multi-layer diode in series therewith so that when anydetector switch is closed, said selected voltage iS clamped to a lesservalue ineffective to allow conduction of any diode in the remainingdetector circuits.